Here's the celebrity roll call for the teen and young adult crowd, the 25 hottest stars under 25 as designated by Teen People magazine.

From Justin Timberlake to Jesse McCartney; Jessica Simpson to Jessica Alba; the Olsens to the O.C., this is a comprehensive look at the Hollywood hot shots and top musical acts everyone is--or will be--talking about. Two of them aren't even people. They're a TV show and a movie!

The names, presented by Teen People alphabetically by first name, aren't ranked. No. 1 is just as popular as No. 25 in the eyes of this list. The asterisk means it's the first time on the list.

Teen People's 25 hottest are:

Alicia Keys, 25
Ashlee Simpson, 20
Avril Lavigne, 20
Britney Spears, 23
Chad Michael Murray, 23
Ciara, 19*
Destiny's Child
Elijah Wood, 24*
Jake Gyllenhaal, 24
Jesse McCartney, 18*
Jessica Alba, 24
Jessica Simpson, 24
Justin Timberlake, 24
Hayden Christensen, 24*
Hilary Duff, 17
Kelly Clarkson, 23*
Kirsten Dunst, 23
Lindsay Lohan, 19
"Lords of Dogtown"*
Natalie Portman, 24
Paris Hilton, 24*
Scarlett Johansson, 20
The Olsens, 19
"The O.C."
T.I., 24*

Fun facts about this list:

• Justin Timberlake: Justin can only make this list one more time before he's too old. Chances are he will. He's been on it five times since 2000.

• Jesse McCartney: Teen People thinks he may be Justin's heir apparent. He's only 18 and on the list for the first time this year.

• "The O.C.": The cast of TV's "it" show makes its second "25 Hottest" appearance without Ben McKenzie who is 26 and in that "too old" category.

• Lindsay Lohan: This "it" girl makes her second appearance on the list after moving from the big screen to music. She's bounced back from controversy to remain one of the hottest stars around.

• Ashlee Simpson: Ashlee seems to have rebounded from a "Saturday Night Live" flop and "Orange Bowl" boos to sell millions of albums and sell out a headlining tour.

• Destiny's Child: How many groups can have all its members go solo only to reunite to come back bigger than ever?

• T.I.: The hottest new rapper is on his way to multi-platinum status. He's also started a clothing line and a construction company that builds low-cost housing.