In our research, we analyze the group conversation in Twitter via. second screen concerning two popular US based TV shows, categorize the postings into four different classifications, and investigate the predominant categories for group interactions. The group conversations are identified by hashtags present in tweets where the number of members in the group interacting is at least two. The classifications are 1) response, 2) referral, 3) broadcast and 4) retweet. We collect nearly 354,000 tweets for these two TV programs. Using oneway analysis of variance, we examine the four tweet categories collected during second screen based group interactions. Our findings indicate that most group-based interaction occurs when the TV show is not being transmitted. The prevalent conversational pattern observed is referral tweets. There are many implications for those interested in understanding social conversation around mass media in the emerging second screen environment.