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In addition to Transformers 4, Sony’s The Amazing Spider-Man 2, Lionsgate’s Divergent and DreamWorks’ Need for Speed are conducting chemistry reads or about to begin testing actors. Need for Speed and Divergent offer the chance to co-star in a movie that could be the next Hunger Games, while Transformers 4 and Spider-Man 2 offer high-profile supporting roles in guaranteed blockbusters that could prove to be career launchpads.

Sources tell The Hollywood Reporter that Transformers 4 has a story that centers on Wahlberg's character and his daughter. In addition, the daughter’s boyfriend, a race car driver, is the third lead in the film.

Testing for the daughter and boyfriend roles is set for this week. Among those vying for the female role are Isabelle Cornish, sister of Australian actress Abbie Cornish (Limitless); Nicola Peltz, who appeared in M. Night Shyamalan’s Paramount movie The Last Airbender and has a part in A&E’s Bates Motel; Margaret Quallay, the daughter of actress Andie MacDowell; and Gabriella Wilde, who is in the new Carrie movie. Alex Frnka, who appears on MTV's The Inbetweeners, is also testing.

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There are five young men testing: Luke Grimes, who appeared on ABC's Brothers & Sisters and is in Taken 2; Landon Liboiron, who co-starred on Fox's Terra Nova and will be seen in the upcoming Netflix series Hemlock Grove; Australian Brenton Thwaites, who starred in the telefilm Blue Lagoon: The Awakening; relative newcomer Jack Reynor; and Weeds co-star Hunter Parrish.

Sources say Paramount is signing actors to strict three-picture deals, but no one is balking because the chance to be the next Shia LaBeouf is seen as a huge opportunity.

At the same time, Spider-Man 2 is looking for its Harry Osborn, the college-aged kid who befriends Peter Parker but ultimately becomes Spider-Man’s deadliest enemy. James Franco played the part in the Sam Raimi trilogy. By bringing gravitas to what easily could have been a second-banana role, Franco parlayed the movies into a significant film career -- and an Oscars co-hosting gig.

The Osborn part, which originally called for a bigger, athletic actor, is being reconfigured and now is targeting a more “dark and edgy" actor, according to two insiders. Names bandied about include Brady Corbet (Melancholia), Dane DeHaan (Chronicle) and Alden Ehrenreich (the upcoming Beautiful Creatures), though there could be other names in the mix because the character is evolving.

Divergent, which Lionsgate hopes will carry the torch as a new Hunger Games- or Twilight-style franchise, is narrowing the list for its male lead, and director Neil Burger is beginning to read some actors to play the young man who trains and falls for the heroine, being played by Shailene Woodley.

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Thwaites and Reynor are said to be in the mix for that role as well.

DreamWorks' Speed, meanwhile, which already has cast Aaron Paul (Breaking Bad) and Imogen Poots as leads, is looking for young male actors to play the other racers.

The upcoming castings are being closely watched by agents and execs because they could signal Hollywood's next attempt to create stars. Insiders lament that there are few actors coming up in the 20-to-30 age bracket who appear to be the heirs of Channing Tatum, Franco or Tom Hardy, who themselves are still trying to find the success minted by Leonardo DiCaprio and Brad Pitt.

Email: Borys.Kit@thr.com

Twitter: @Borys_Kit